Train stop system



Sept. 27, 1932. A. E. HUDD TRAIN STOP SYSTEM Original Filed Hay .'51, 1928 2 Sheets-Sheet '1 @Innen ur'- FllfTEdE-Iudd sept. 27,1932. A. E. Hunn 1,87*611 l TRAIN sTQP SYSTEM A Original Filed May 31, 1928 2 Sheets-Sheet 2 Ellred E Hudd Patented Sept. 27, 1932 ALFRED n. HUDD, oF LONG PARK, cnn

snaar BoIs, ENGLAND, AssIGNon, BY MESNE ASSIGNMENTS, TO `ASSOCIATED ELECTRIC LABORATORIES., INC., OF 4CHICAGO,IIILLI NOIS, A CORPORATION QFY1')IECUAYHIARE.`

mam sror snrsriiaz ApplioationMedLIayL 1898, Serial No. 251,616. Renewed March 23, 1932i.

The present invention relates in 4general to train control systems, but is particularly concerned with the'development of an automanual train stop system ofthe intermittent inductive type, and may be considered as a `valve 2, normally held further development of the t pe of system disclosed in the co-pending udd application, Serial N o. 213,455, filedAugust 17, 1927.

VOne of the principal objects of the present invention is to further simplify and improve the design of the equipment, making it more reliable and more economical to build and maintain.

Another object is to arrange theapparatus i z in such a manner that no single unit of the same is of such bulk as to render installation, especially in the cab of the vehicle, diilicult. This is accomplished in the `present case by substituting a number of small units for a large casting, formerly servingas a structure for these units. l,

A further feature covers an arrangement for suspending the vehicle relay or receiver in a simple manner and providing in consjunction therewith means for detecting anyl movement of thereceiver with respectV to the vehicle should an obstruction be encountered by the receiver to move it out of active relation with the trackway elements.

Other objects of the invention not lparticularly pointed out will becomeobvious as the specific description of the invention proceeds.

riihc invention is disclosed in two sheets of drawings. Fig. 1 diagrammatically discloses the mechanism and circuits of the locomotive equipment and one set of associated trackway elements, while Figs. 2 and 2A are views, in elevation, of the carrier and housing for'the locomotive receiver relay assembly.

The vehicle equipment, as shownin Fig'l, consists of an applicator havingan arm 30', through the medium of which the engineer may at any time manually apply the brakes of the vehicle in the usual and well known manner. This applicator is equipped with a pneumatically operable piston 6 for bringing about an automatic brake application under certain conditions. An electropneumatic closed by its energized winding, is effective, upon deenergization, to

of air at 40 lbs.

release the air pressure stored up in two reservoirs B and C through the whistle 5, to warn the-enginemanof the fact that a signal as been passed and to ultimately bring about a brake application unless the electropneumatic valve 2 is again energized `within a predetermined interval as will subsequently be described. A light'lcontrol relay 50`is provided for and functions in conjunction with the armatures and contacts of a receiver relay R and with the contacts of a pneumatic contactor PC to maintain the appropriate lamp G or P lighted in accordance with traffic conditions. i

The receiverR- is a polarized rela along the general lines` ofthe one disclose in the co-pending application previously referred to, but is slightly diiierentin that it has two independently controlled armatures. The

trackway devices, diagrammatically shown,

comprise a permanent magnet 41 and an electro-magnet, 42, placed approximately six' feet from each other at the-exit end of a block. A semaphore signal issalso shown indicating clear conditions,v and for simplicitys sake, indicating that it directly completes the circuit for the electromagnet trackway element 42 when in this position only. In actual practice, however, the use of a circuit control system of the type shown in Fig. 3 of theco-pending application Serial No. 213,- 455, is contemplated. y

i The pneumatic contactor consists of a casting 34 on which is mounted a disk 13 of leather, rubber, or other suitable material provided with a Contact operating button 44. Also suitably mounted upon this casting is a contact arm 14 and associatedlower and upper contact elements. A cover 35 completely encloses and protects the contact il part` of the casting mechanism. The lower 34 has a number of perforations 43 surrounding the perforations to pipes 33; and 28 are connected. The contact mechanism andvarious apertures are so dei 'l signed that a pressure pulse of 40 lbs. or over through the pipe 33 or a continued flow pressure through the pipe 28 will be required to actuateY the arm 14.

`The stop detector unit4 SD is of the type which the connecting i shown and described in a co-pending Hudd application, Serial No. 274,412, and filed May 2, 1928. This stop detector, as described in the cof-pending application referred to, functions in response tothe application of air to pipe 45 to apply air to the pneumatic contactor PC, via pipe 28, only in case the locomotive wheel 31, associated with element 21, is stationary Yat .the time pressure is" applied to the stop detector, all 'as clearly described in the co-pen'ding application referred to.

The various devices on the vehicle V as shown in Fig. 1 are in their normal operating positions, thatis, the positions assumed when the equipped vehicle is traveling under clear traffic conditions with all circuits and devices properly energized. For convenience, the wellv known positive land negative symbols have been used to designate the opposite poles of a source of energy, preferably a storage battery, generator, ora suitable combination of the .'two.

In order to explain the invention it will first be assumed that a vehicle is equipped with the apparatus and circuits of Fig. 1 and is operating under clear traffic conditions, as indicated bythe semaphore S.

VThe armatures 58 and 59 of the receiver relay R are normally polarized by the permanent magnet P. lt will therefore be obvious that the normal magnetic circuits are such that the armatures are magnetically biased by the presence of the permanent magnetV P to either of their pole pieces to Ywhich they have been attracted.

0 partition l When a train approaches the exist of a block the pole pieces 43 and 44 first pass over and within inductive relation to the trackway magnet 41 and then the pole pieces 41 and 42 pass over this magnet. The polarity of magnet 41 is such that it weakens the attractive effect between armature 58 and the pole piece 44 produced by magnet P and strengthens the attractive effect between this armature and ofthev pole piece 43,vwhich causes armature 58 to be rotated in a clockwise direction, thereby opening its lower and closing its upper contacts. As the vehicle proceeds pole pieces 41 and 42 come under the influencel of the magnet 41 and armature 59 is alsocaused to rotate in afclockwise direction, to open its upper and close its lower contacts.

o The armature 58, at its lower contact, breaks a normally established circuit for the electropneumatic valve 2 which releases and permits air to exhaust through the whistle 5.

kThis circuit formerly extended from the negative terminal, through the armature 58 and its lower contact, conductor 51, the winding` of the electropneumatic valve 2, conductor. 52, triangular plate 47, tobe later de'- scrihed, upper contact and armature 59 and thence to the positive terminal. The armature v59, in operating, at its upper contact opens a second point in the traced circuit for the electropneumatic valve 2, and in addition, at its lower contact completes an operating circuit for the light control Vrelay 50 via conductor 3. However, the closure of this circuit is without effect at this time as the light relay is already held up over a stick circuit including its contacts 8 andthe lower contact and lever 14 of the pneumatic contactor'PC.

A circuit for the gre-en lamp G normally maintained inl multiple with the electropneumatic valve 2, also includes conductors 53 andl 54, and contacts 10 of the light control relay 50. Since the lamp G is in multiple with the electropneumatic valve 2, the instant that the elements 43 and 44 of the receiver/relay R- pass over a permanent magnet, such as 41, not only is the electropneumatic valve deenergized, but in addition the green light G is extinguished. u

` As soon as the train travels approximately the trackway magnet 41, the receiver passes over the electromagnet traclrway clement 42, which, under the condition assumed, is energ'ized.y The electromagnet 42 is of a polarsix feet, after the receiver has encountered 'l i ity opposite to that of the permanent magl i net and therefore functions to restore the armatures 58 and 59 to their initial positions, in which they are shown. This causes the formerly traced multiple circuit for the electropneumatic 'valve 2 and green lamp G to be again completed. The effect of passing over these'magnets therefore, under the circumstances assuined,iis to' cause the warning whistle of the electropneumatic valve to be Aactuated momentarily and give a toot, so to 'f7- speak, and inthe green lamp being extinguished momentarily. The operation of these signals in this manner serves to notify the engineer both audibly7 and visibly, that the vehicle has passed a proceed signal and has therefore entered a block in which traffic conditions are favorable. Y

Ivwill now assume 'that the train has arrivednear the exit of va block at which the signal'S is in its caution or stop7 position. With this state of affairs existing, when the receiver R pass-es over the permanent magnet 41 the foregoing described circuit changes take place as before. iowever, since the electromagnet 42 is deenergized at this time, the circuit conditions brought about by magm net 41 will remain unchanged. Consequently the electropneumatic valve 2 will remain deuenergized and the warning whistle 5 will continuato sound. Also, the green light G will remain extinguished.

Main reservoir pressure is normally maintained in the reservoirs B and G through restricted orifices 12 and 13, respectively, and

the size of the B reservoir, restricted orifice "il which will respond and operate the lever 14 into engagement with its upper contact.

Owing to the limited capacity of the reservoir C and due to the restricted orifice 1 3, lever 14 can however be only actuated momentarily by an actuation ofthevalve G1. Lever 14 in operating completes a circuit from the positive terminal, through the lever 14 and its upper contact, conductor 55, and to and through the windings 17 and 18 ofthe receiver R to the negative terminal. rThese windings, when energized are effective to swing the armatures 58 and 59back to their initial positions. A further result which occurs responsive to the momentary raising of lever 14 of pneumatic contactor is the breaking, at thelower contact of lever 14, of the holding circuit of the light control relay 50, which therefore drops its armature as soon as the armature 59 is restored. Relay at its contacts 11 now completes a circuit for the purple lamp P in f multiple withthe electrop-neumatic valve 2 instead of for thelamp G. The lighted condition of the purple lamp Vserves to warn the engineer that he is about to pass through a block under restricted traffic conditions.

If for any reasonv whatever theeengine'er fails to operate` the acknowledging valve l61 during the six second period the pressure drop in reservoir C will be such that an operation of the acknowledging .lever 61 will be without effect to cause the movement of the lever 14. Also, the pressure in reservoir B will be insufficient to maintain the valve element 1 in closed position. This valve element will therefore move tothe right and permit main reservoir pressure to be supplied to the piston 6, causng a service application of the brakes to be made. Y

The engineer cannot removethe brake application until the vehicle has actually been brought to a stop, for, as previously explained, the actuation of the acknowledging valve G1 will be without Aeffect `owing to the drop in pressure in reservoir C caused by th exhaust through whistle for more than the six second interval.

1VVhen the vehicle has been brought toa stop the engineer lmay cutolfthe application of air being supplied to the actuator piston 6 by actuating the stopv detector valve 16. The actuation of this valve permits in ainreservoir -valve 2, the

pressure to be applied to the stop detector SD which functions to open up a passage permitting main reservoir pressure to be applied to the pneumatic contactor via, pipe 28 if, and only if the vehicle isat a standstill, as clearly brought out in the co-pending application Serial No. 274,412, formerly referred to. The lever 14, upon operating, atits lowercontact breaks thestick circuit of relay 50 and at its Aupper contact completes the previously traced circuit for causing the armatures 58 and 59 to be restored to again complete the circuit for the electropneumatic valve 2. The armature 59, upon being restored also, at its lowercontact now breaks the energizing circuit of the light control relay, which drops its armature before'lever 14 can again close the stick cir-y cuit' The relay 50 thereforel at its contacts 11 now completes a circuit for the Vpurple lamp P.' Itwill be seen therefore that Valthough the train can proceed as soon as the pressure in reservoir B becomes high enough Y to restore the valve 1, as occurs shortly following the reenergization of the electropneumatic purple lamp will remain lighted to continuallv warn the engineer that he is in caution territory.

I will now assume that the vehicle is again about to enter a block in which favorable traiiic conditions exist. Under these conditions, when the receiver passes over the permanent magnet 41 the armatures 58 and -59 are moved to their alternate positions as be-l fore with thesame results, and the light control relay is again energized by thecircuit completed for it through armature 59. The purple lamp is therefore extinguished, but

the circuit of the green light is not yet complet-ed owing to the alternate position of armature 58. An instant later, however, when the receiver passes over the energized electromagnet 42, armatures 58 and 59 are again restored to their initial position, again completing the circuit of the electropneumatic valve 2 and of the green lamp G. The light control relay does not become deenergized now even though its energizing circuit is again broken at the lower contact of armature 59 because a stick circuit was completed upon itsenergization through its contacts V8 and through the lower Contact and lever 14 of the pneumatic contacter. The vehicle equipment is therefore in the same condition as it originally was when the description of the operation was begun, under the assumption that Vthe vehicle was traveling in clear territory.

On certain installations it may be desirable to provide means for checking up the number of times the receiver relay is operated. This is accomplished in the present case by connecting a meter 37:'to the upper contact of armature 58 of the receiver relay. VThe time at which acknowledgement is madev is also recorded by the recorder 31', which is lconnected directly to the conductor leading to the upper contact of the pneumatic contactor.

Referring to Figs. 2 and 2A, the type of Vreceiver carrier employed in the present system will be explained. A pair of brackets 6() are securely fastenedto the trame of the tender and to these are! secured two triangular plates 47 and 48, which are held in e place by la bolt '49. To the plates 47 and 48 are secured, by machine screws 62, the housing 57 having a cover 56 which encloses the relay or receiver relay apparatus It, diagrammatically shown in Fig. 1. The particular feature of thisfmethod of carrying the're'ceiver relay has to do with a protective arrangement for ,guarding against the receiver `unit being pushed out ot inductive -relation by a track obstruct-ion without the knowledge of the engineer. vThis is accomlplished by making perforations in the plate 47v and the associated bracket 60 which are in alignment when'the receiver unit is vin the proper relation to the trackway. These is shown as passing through the perforation in the plate 47 and bracket 60 several out the conductors may he brought through same, to obtain further protection, or a similar arrangement may beV provided between the plate 48 and its associated bracket.

That IV claim is:

1. In a'cab signal system, a pair of lamp signals, a normally energized relay having a pair of normally closed contacts included in a circuit including one of said signals and having another pair of normally Open con tacts included in a circuit including the sec ond signal of the pair, a secondrelay having a pair of normally closed contacts included in a circuit common to both oi"V said lamp signals, means for actuating said second relay, thereby breaking the common circuit for said signals and other means for then ac tuating the first and restoring the second re lay to complete the circuit kof the second lamp signal of said pair.

2. In a cab signal system, a normally energized light cont-rol relay a signal having a circuit including normally closed contacts of said relay, a second signalhaving a circuit `including normally opencontacts of said relay, other means on the vehicle under control of trackway means to cause the said light control relay to become dei/energized and open the circuit of the irst signal and close `nar/9,811

a point in the circuit of the second signal and manually operable means for causing the actuation of said other means to complete the circuit of said second signal.

3. In a cab signal system, a cab carried relay, a cab signal and a circuit therefor completed while the vehicle is traveling under clear traiic conditions, means for inductively actuating said relay to extinguish said sig nal, means for again inductively actuating said relay to again light said signal, other means for actuating said relay, and a second relay controlled by said other means to prevent the signal being lighted in the latter instance. l

4. In a train control system, trackway equipment comprising a permanent and an electromagnet at the exit end of each block section, a cab equipped with a. receiver relay having two armatures separably operable by magnetic influences transmitted to the receiver byr each of said magnets, and train control equipment controlled by said armatures. n

Y 5. In a train stop system, a. receiver relay, means for suspending said receiver relay under a vehicle in operative relation with trackway elements and a train control circuit passl ing through perforations in said means, the material surrounding said perforations functioningv as shears for severing said circuit should the receiver be moved out of operating relation with said trackway elements.

6. In a train stop system, an impulse receiver suspended from a vehicle, electrical conductors extending between said vehicle and receiver, and means for shearing one of said conductors consequent to movement of said receiver relative tol the vehicle .7. In a train control system, a normally energized relay and magnet respectively, lamp signa-ls under control of said relay, means for causing a change in the condition of one of said lamp signals and to visually and aud-v ibly warn an engineman of a changed trailic condition, means controlled by an engineman for causing the reenergization of said magnet, and auxiliary means also effective, incidental to the actuation necessary to reenergize said. magnet, to interrupt the circuit oi said relay to further modify the condition of one of said lamp signals.

8. In a cab signal system, a pair of lamp signals, a vehicle carried pickup relay and a light control relay, respectively, circuits for said lamp signals including contacts of said relays, trackway means for causing the pickup relay to operate and interrupt the circuit of one of said signals, and manually controlled means for causing the circuit ot said lightcontrol relay to be interrupted and the pickup relay to be again operated to complete the circuit of said other lamp signal.

9. In an automatic train stop system, an electro-pneumatic valve and a signal control signals and to at the same time cause the reestablishment of the valve circuit.

l0. In a cab signalling system, a pair 'of signals, a relay, a holding eircuitover Which said relay is normally maintained energized,

contacts on said relay in a normally closed circuit including one of said signals, other contacts on said relay in a normally open circuit including the other of said signals, a second relay having a pair of normally'closed contacts included in a circuit common to said signals, means for actuating said second relay to break the common f circuit and thereby retire either signal Which may at the time be active, and manually controlled means for interrupting the holding circuit of said irst relay to cause it to close a point in the normally open signal circuit and for establishing a restoring cir-cuit for said second relay to thereby cause it to operate and complete the circuit of the other of said signals.

11. In a train control system, a receiver relay operable independently of and also in accordance with traffic conditions vehicle signals for displaying non-restrictive and restrictive indications, respectively; a normally energized control relay `for assisting said receiver relay in the control of said vehicle signals, an energizing circuit for said signal control relay controlled exclusively by said receiver relay, a manually controlled means for varying the signal control effect caused by an actuation of said receiver relay, and a holding circuit for said signal control relay controlled exclusively by'said manually controlled means.` v

12. In a train control system; a vehicle equipped with signals vfor displaying nonrestrictive and restrictive indications displayed by signals associated With the track- Way, vehicle carried means operated Whenthe vehicle encounters a Wayside signal for retiring the active one of said vehicle signals ir-V respective of which signal is active, means for then automatically rendering one of'said vehicle signals active if the encountered Wayside signal is displaying a non-restrictive indication, a normally energized relay for preventing the other vehicle signal from be` coming active at such time, manually controlled means effective, vvvhen operated, to deenergize said relay to render the other vehicle signal active if thev ,encountered signal is displaying a restrictive indication, and means fgr causing an automatic brake appli-l cation to occur if the prompt operation of said manually controlled means is neglected under the latter circumstances.

13. In a cab signalling system, the cornbination With a vehicle and trackway, of nonrestrictive and restrictive signals in the vehicle, a double armature pickup relay suspended from the vehicle, permanent and electromagnet track elementsV for operating the armatures of said relay, a manually controlled normally open operating circuit for also operating the armatures of said pickup relay, another relay on the vehicle, and circuit con- V.nections Within the vehicle controlled jointly by `said relays and by said manually controlled circuit for substantially constantly maintaining the appropriate signal active.

In Witness whereof, I hereuntoV subscribe my name this th day of May, A. D. 1928. ALFRED E. HUDD. 

